Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 1 | /* GSM silent call feature */ |
| 2 | |
| 3 | /* |
| 4 | * (C) 2009 by Harald Welte <laforge@gnumonks.org> |
| 5 | * |
| 6 | * All Rights Reserved |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or modify |
Harald Welte | 9af6ddf | 2011-01-01 15:25:50 +0100 | [diff] [blame] | 9 | * it under the terms of the GNU Affero General Public License as published by |
| 10 | * the Free Software Foundation; either version 3 of the License, or |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 11 | * (at your option) any later version. |
| 12 | * |
| 13 | * This program is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
Harald Welte | 9af6ddf | 2011-01-01 15:25:50 +0100 | [diff] [blame] | 16 | * GNU Affero General Public License for more details. |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 17 | * |
Harald Welte | 9af6ddf | 2011-01-01 15:25:50 +0100 | [diff] [blame] | 18 | * You should have received a copy of the GNU Affero General Public License |
| 19 | * along with this program. If not, see <http://www.gnu.org/licenses/>. |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 20 | * |
| 21 | */ |
| 22 | |
| 23 | #include <stdlib.h> |
| 24 | #include <unistd.h> |
| 25 | #include <errno.h> |
| 26 | |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 27 | #include <osmocom/core/byteswap.h> |
Pablo Neira Ayuso | 136f453 | 2011-03-22 16:47:59 +0100 | [diff] [blame] | 28 | #include <osmocom/core/msgb.h> |
Philipp Maier | 9286114 | 2019-03-15 09:43:40 +0100 | [diff] [blame] | 29 | #include <osmocom/core/utils.h> |
Neels Hofmeyr | 9084396 | 2017-09-04 15:04:35 +0200 | [diff] [blame] | 30 | #include <osmocom/msc/signal.h> |
| 31 | #include <osmocom/msc/debug.h> |
Neels Hofmeyr | 9084396 | 2017-09-04 15:04:35 +0200 | [diff] [blame] | 32 | #include <osmocom/msc/gsm_data.h> |
| 33 | #include <osmocom/msc/gsm_subscriber.h> |
Neels Hofmeyr | d656dff | 2018-03-09 14:59:44 +0100 | [diff] [blame] | 34 | #include <osmocom/msc/vlr.h> |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 35 | |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 36 | #include <osmocom/sigtran/sccp_helpers.h> |
| 37 | |
| 38 | struct silent_call_data { |
| 39 | struct gsm0808_channel_type ct; |
| 40 | |
| 41 | char traffic_ip[INET_ADDRSTRLEN]; |
| 42 | uint16_t traffic_port; |
| 43 | |
| 44 | void *data; |
| 45 | |
| 46 | struct osmo_timer_list timer; |
| 47 | struct ran_conn *conn; |
| 48 | }; |
| 49 | |
| 50 | static void timer_cb(void *data) |
| 51 | { |
| 52 | struct silent_call_data *scd = (struct silent_call_data *)data; |
| 53 | ran_conn_communicating(scd->conn); |
| 54 | talloc_free(scd); |
| 55 | } |
| 56 | |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 57 | /* paging of the requested subscriber has completed */ |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 58 | static int paging_cb_silent(unsigned int hooknum, unsigned int event, |
Holger Hans Peter Freyther | 86481c2 | 2010-06-17 15:05:57 +0800 | [diff] [blame] | 59 | struct msgb *msg, void *_conn, void *_data) |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 60 | { |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 61 | struct silent_call_data *scd = (struct silent_call_data *)_data; |
Neels Hofmeyr | c036b79 | 2018-11-29 22:37:51 +0100 | [diff] [blame] | 62 | struct ran_conn *conn = _conn; |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 63 | struct scall_signal_data sigdata; |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 64 | struct msgb *msg_ass; |
Holger Hans Peter Freyther | a97152b | 2010-07-23 19:34:34 +0800 | [diff] [blame] | 65 | int rc = 0; |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 66 | int i; |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 67 | |
| 68 | if (hooknum != GSM_HOOK_RR_PAGING) |
| 69 | return -EINVAL; |
| 70 | |
Holger Hans Peter Freyther | eff40949 | 2012-11-10 19:46:58 +0100 | [diff] [blame] | 71 | DEBUGP(DLSMS, "paging_cb_silent: "); |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 72 | |
Holger Hans Peter Freyther | 86481c2 | 2010-06-17 15:05:57 +0800 | [diff] [blame] | 73 | sigdata.conn = conn; |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 74 | sigdata.data = scd->data; |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 75 | |
| 76 | switch (event) { |
| 77 | case GSM_PAGING_SUCCEEDED: |
Neels Hofmeyr | e2f24d5 | 2017-05-08 15:12:20 +0200 | [diff] [blame] | 78 | #if BEFORE_MSCSPLIT |
| 79 | /* Re-enable this log output once we can obtain this information via |
| 80 | * A-interface, see OS#2391. */ |
Holger Hans Peter Freyther | eff40949 | 2012-11-10 19:46:58 +0100 | [diff] [blame] | 81 | DEBUGPC(DLSMS, "success, using Timeslot %u on ARFCN %u\n", |
Holger Hans Peter Freyther | 86481c2 | 2010-06-17 15:05:57 +0800 | [diff] [blame] | 82 | conn->lchan->ts->nr, conn->lchan->ts->trx->arfcn); |
Neels Hofmeyr | e2f24d5 | 2017-05-08 15:12:20 +0200 | [diff] [blame] | 83 | #endif |
Holger Hans Peter Freyther | 68884aa | 2010-03-23 06:41:45 +0100 | [diff] [blame] | 84 | conn->silent_call = 1; |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 85 | |
| 86 | /* Increment lchan reference count and mark as active*/ |
Neels Hofmeyr | 3c20a5e | 2018-11-30 01:08:36 +0100 | [diff] [blame] | 87 | ran_conn_get(conn, RAN_CONN_USE_SILENT_CALL); |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 88 | |
| 89 | /* Schedule a timer to mark it as active */ |
| 90 | /* This is a hack we we can't call ran_conn_communicating |
| 91 | * from here because we're in the call back context of |
| 92 | * a RAN FSM event but before it actually changes its own |
| 93 | * state and it's not ready to accept this. |
| 94 | * Of all alternatives considered, making the call in an |
| 95 | * 'immediate timer' is the least disruptive and least ugly |
| 96 | * way to do it I could find. |
| 97 | */ |
| 98 | scd->conn = conn; |
| 99 | osmo_timer_setup(&scd->timer, timer_cb, scd); |
| 100 | osmo_timer_schedule(&scd->timer, 0, 0); |
| 101 | |
| 102 | /* Manually craft an assignement message with requested mode */ |
| 103 | if (scd->ct.ch_indctr == GSM0808_CHAN_SPEECH) { |
| 104 | struct gsm0808_speech_codec_list scl; |
| 105 | union { |
| 106 | struct sockaddr_storage st; |
| 107 | struct sockaddr_in in; |
| 108 | } rtp_addr; |
| 109 | |
| 110 | memset(&rtp_addr, 0, sizeof(rtp_addr)); |
| 111 | rtp_addr.in.sin_family = AF_INET; |
| 112 | rtp_addr.in.sin_port = osmo_htons(scd->traffic_port); |
| 113 | rtp_addr.in.sin_addr.s_addr = inet_addr(scd->traffic_ip); |
| 114 | |
| 115 | for (i = 0; i < scd->ct.perm_spch_len; i++) |
| 116 | gsm0808_speech_codec_from_chan_type(&scl.codec[i], scd->ct.perm_spch[i]); |
| 117 | scl.len = scd->ct.perm_spch_len; |
| 118 | |
| 119 | msg_ass = gsm0808_create_ass(&scd->ct, NULL, &rtp_addr.st, &scl, NULL); |
| 120 | } else { |
| 121 | msg_ass = gsm0808_create_ass(&scd->ct, NULL, NULL, NULL, NULL); |
| 122 | } |
| 123 | |
| 124 | /* Send assignement message, hoping it will work */ |
| 125 | osmo_sccp_tx_data_msg(conn->a.scu, conn->a.conn_id, msg_ass); |
| 126 | |
| 127 | /* Signal completion */ |
Pablo Neira Ayuso | bbc5b99 | 2011-05-06 12:12:31 +0200 | [diff] [blame] | 128 | osmo_signal_dispatch(SS_SCALL, S_SCALL_SUCCESS, &sigdata); |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 129 | return 0; |
| 130 | |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 131 | case GSM_PAGING_EXPIRED: |
Holger Hans Peter Freyther | d3baf41 | 2010-12-23 18:19:17 +0100 | [diff] [blame] | 132 | case GSM_PAGING_BUSY: |
Holger Hans Peter Freyther | eff40949 | 2012-11-10 19:46:58 +0100 | [diff] [blame] | 133 | DEBUGP(DLSMS, "expired\n"); |
Pablo Neira Ayuso | bbc5b99 | 2011-05-06 12:12:31 +0200 | [diff] [blame] | 134 | osmo_signal_dispatch(SS_SCALL, S_SCALL_EXPIRED, &sigdata); |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 135 | break; |
| 136 | default: |
| 137 | rc = -EINVAL; |
| 138 | break; |
| 139 | } |
| 140 | |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 141 | talloc_free(scd); |
| 142 | |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 143 | return rc; |
| 144 | } |
| 145 | |
Philipp Maier | e0d5caa | 2017-02-27 16:56:59 +0100 | [diff] [blame] | 146 | #if 0 |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 147 | /* receive a layer 3 message from a silent call */ |
Neels Hofmeyr | c036b79 | 2018-11-29 22:37:51 +0100 | [diff] [blame] | 148 | int silent_call_rx(struct ran_conn *conn, struct msgb *msg) |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 149 | { |
| 150 | /* FIXME: do something like sending it through a UDP port */ |
Jacob Erlbeck | 8e68b56 | 2014-01-30 21:01:12 +0100 | [diff] [blame] | 151 | LOGP(DLSMS, LOGL_NOTICE, "Discarding L3 message from a silent call.\n"); |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 152 | return 0; |
| 153 | } |
| 154 | |
| 155 | struct msg_match { |
Holger Hans Peter Freyther | c42ad8b | 2011-04-18 17:04:00 +0200 | [diff] [blame] | 156 | uint8_t pdisc; |
| 157 | uint8_t msg_type; |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 158 | }; |
| 159 | |
| 160 | /* list of messages that are handled inside OpenBSC, even in a silent call */ |
| 161 | static const struct msg_match silent_call_accept[] = { |
| 162 | { GSM48_PDISC_MM, GSM48_MT_MM_LOC_UPD_REQUEST }, |
| 163 | { GSM48_PDISC_MM, GSM48_MT_MM_CM_SERV_REQ }, |
| 164 | }; |
| 165 | |
| 166 | /* decide if we need to reroute a message as part of a silent call */ |
Neels Hofmeyr | c036b79 | 2018-11-29 22:37:51 +0100 | [diff] [blame] | 167 | int silent_call_reroute(struct ran_conn *conn, struct msgb *msg) |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 168 | { |
| 169 | struct gsm48_hdr *gh = msgb_l3(msg); |
Neels Hofmeyr | 531734a | 2016-03-14 16:13:24 +0100 | [diff] [blame] | 170 | uint8_t pdisc = gsm48_hdr_pdisc(gh); |
| 171 | uint8_t msg_type = gsm48_hdr_msg_type(gh); |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 172 | int i; |
| 173 | |
| 174 | /* if we're not part of a silent call, never reroute */ |
Holger Hans Peter Freyther | 758f4df | 2010-06-21 10:34:03 +0800 | [diff] [blame] | 175 | if (!conn->silent_call) |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 176 | return 0; |
| 177 | |
| 178 | /* check if we are a special message that is handled in openbsc */ |
| 179 | for (i = 0; i < ARRAY_SIZE(silent_call_accept); i++) { |
| 180 | if (silent_call_accept[i].pdisc == pdisc && |
Neels Hofmeyr | 531734a | 2016-03-14 16:13:24 +0100 | [diff] [blame] | 181 | silent_call_accept[i].msg_type == msg_type) |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 182 | return 0; |
| 183 | } |
| 184 | |
| 185 | /* otherwise, reroute */ |
Jacob Erlbeck | 8e68b56 | 2014-01-30 21:01:12 +0100 | [diff] [blame] | 186 | LOGP(DLSMS, LOGL_INFO, "Rerouting L3 message from a silent call.\n"); |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 187 | return 1; |
| 188 | } |
Philipp Maier | e0d5caa | 2017-02-27 16:56:59 +0100 | [diff] [blame] | 189 | #endif |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 190 | |
| 191 | |
| 192 | /* initiate a silent call with a given subscriber */ |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 193 | int gsm_silent_call_start(struct vlr_subscr *vsub, |
| 194 | const struct gsm0808_channel_type *ct, |
| 195 | const char *traffic_dst_ip, uint16_t traffic_dst_port, |
| 196 | void *data) |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 197 | { |
Holger Hans Peter Freyther | b618c7e | 2015-08-03 11:21:29 +0200 | [diff] [blame] | 198 | struct subscr_request *req; |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 199 | struct silent_call_data *scd; |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 200 | |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 201 | scd = talloc_zero(vsub, struct silent_call_data); |
| 202 | |
| 203 | memcpy(&scd->ct, ct, sizeof(scd->ct)); |
| 204 | |
| 205 | if (traffic_dst_ip) { |
Philipp Maier | 9286114 | 2019-03-15 09:43:40 +0100 | [diff] [blame] | 206 | osmo_strlcpy(scd->traffic_ip, traffic_dst_ip, sizeof(scd->traffic_ip)); |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 207 | scd->traffic_port = traffic_dst_port; |
| 208 | } |
| 209 | |
| 210 | scd->data = data; |
| 211 | |
| 212 | req = subscr_request_conn(vsub, paging_cb_silent, scd, |
Harald Welte | 0df904d | 2018-12-03 11:00:04 +0100 | [diff] [blame] | 213 | "establish silent call", |
| 214 | SGSAP_SERV_IND_CS_CALL); |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 215 | if (!req) { |
| 216 | talloc_free(scd); |
Neels Hofmeyr | d656dff | 2018-03-09 14:59:44 +0100 | [diff] [blame] | 217 | return -ENODEV; |
Sylvain Munaut | 9355830 | 2019-02-14 20:13:08 +0100 | [diff] [blame] | 218 | } |
| 219 | |
Neels Hofmeyr | d656dff | 2018-03-09 14:59:44 +0100 | [diff] [blame] | 220 | return 0; |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 221 | } |
| 222 | |
Harald Welte | 5100877 | 2009-12-29 11:49:12 +0100 | [diff] [blame] | 223 | /* end a silent call with a given subscriber */ |
Harald Welte | 2483f1b | 2016-06-19 18:06:02 +0200 | [diff] [blame] | 224 | int gsm_silent_call_stop(struct vlr_subscr *vsub) |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 225 | { |
Neels Hofmeyr | c036b79 | 2018-11-29 22:37:51 +0100 | [diff] [blame] | 226 | struct ran_conn *conn; |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 227 | |
Harald Welte | 2483f1b | 2016-06-19 18:06:02 +0200 | [diff] [blame] | 228 | conn = connection_for_subscr(vsub); |
Neels Hofmeyr | d656dff | 2018-03-09 14:59:44 +0100 | [diff] [blame] | 229 | if (!conn) { |
| 230 | LOGP(DMM, LOGL_ERROR, "%s: Cannot stop silent call, no connection for subscriber\n", |
| 231 | vlr_subscr_name(vsub)); |
| 232 | return -ENODEV; |
| 233 | } |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 234 | |
Harald Welte | 83579ca | 2009-12-29 11:17:18 +0100 | [diff] [blame] | 235 | /* did we actually establish a silent call for this guy? */ |
Neels Hofmeyr | d656dff | 2018-03-09 14:59:44 +0100 | [diff] [blame] | 236 | if (!conn->silent_call) { |
| 237 | LOGP(DMM, LOGL_ERROR, "%s: Cannot stop silent call, subscriber has no active silent call\n", |
| 238 | vlr_subscr_name(vsub)); |
| 239 | return -ENOENT; |
| 240 | } |
Harald Welte | 83579ca | 2009-12-29 11:17:18 +0100 | [diff] [blame] | 241 | |
Neels Hofmeyr | e2f24d5 | 2017-05-08 15:12:20 +0200 | [diff] [blame] | 242 | #if BEFORE_MSCSPLIT |
| 243 | /* Re-enable this log output once we can obtain this information via |
| 244 | * A-interface, see OS#2391. */ |
Jacob Erlbeck | 8e68b56 | 2014-01-30 21:01:12 +0100 | [diff] [blame] | 245 | DEBUGPC(DLSMS, "Stopping silent call using Timeslot %u on ARFCN %u\n", |
| 246 | conn->lchan->ts->nr, conn->lchan->ts->trx->arfcn); |
Neels Hofmeyr | e2f24d5 | 2017-05-08 15:12:20 +0200 | [diff] [blame] | 247 | #endif |
Jacob Erlbeck | 8e68b56 | 2014-01-30 21:01:12 +0100 | [diff] [blame] | 248 | |
Holger Hans Peter Freyther | 4049455 | 2010-06-28 17:09:29 +0800 | [diff] [blame] | 249 | conn->silent_call = 0; |
Neels Hofmeyr | 3c20a5e | 2018-11-30 01:08:36 +0100 | [diff] [blame] | 250 | ran_conn_put(conn, RAN_CONN_USE_SILENT_CALL); |
Harald Welte | a148233 | 2009-11-14 10:08:40 +0100 | [diff] [blame] | 251 | |
| 252 | return 0; |
| 253 | } |